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C++
char * p = "hello";
cout<<p; 
cout<<p+1;
cout<<*p;

output
hello
105
h

Can any one explain the first two outputs please?
Posted
Updated 9-Sep-11 10:43am
v2
Comments
Philippe Mori 9-Sep-11 18:27pm    
Are you sure that your second line is 105? If so, your compiler is broken.

Something strange, here:
according to the standard, your compiler and or the standard library aren't standard, or ... you did a typo.

The key is the << operator between cout and the expressions.
p is a char*, and << sends out the sequence of character it points to up to the '\0' implicitly appended to the definition of the "hello" literal (hence, it prints hello).
p+1 is a char* pointing to the next of "h", and works the same as before (hence , should had been printing ello.
*p is a character, and << just prints it.
*p+1 is an expression that evaluates to an integer: *p is the char 'h', and + between a char and an int promotes the char as int and adds the integers. 'h' is 104, adding 1 gives 105 (and it's printed).
 
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v2
Comments
Simon Bang Terkildsen 9-Sep-11 17:31pm    
+5 Glad to hear it was not just me who thought that was strange. Probably a typo or a weird compiler.
Sergey Alexandrovich Kryukov 10-Sep-11 0:08am    
Horse is really around the corner -- I'm not a psycho... :-)
Now we know that "ello" == 105 (a world constant, almost :-)
My 5 to Emilio, too.
--SA
Emilio Garavaglia 10-Sep-11 2:56am    
"Horse is really around the corner": ??? My reference culture does not contain such an expression. What does it mean? (Of course, that's off-topic, do not answer if you find that's not the case!)
[no name] 12-Sep-11 4:20am    
Good one. My 5 too.
1) p is a pointer to a character array and giving it to cout will print the contents as a string
2) p+1 is evaluated as a contents of the first char in the array + 1 ie h=104 + 1
3) *p means the contents of the address the pointer is pointing to which is a character which is h
 
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Comments
Simon Bang Terkildsen 9-Sep-11 16:07pm    
about 2) that must depend on your compiler, as I would expect it to print "ello" and I've just tried it with VC++ and I get "ello". cout<<*p+1; prints 105
Philippe Mori 9-Sep-11 18:26pm    
Effectivelly, it should print "ello". Thus answer #2 is not valid.
Sergey Alexandrovich Kryukov 10-Sep-11 0:10am    
Ha-ha...
--SA
C++

HELLO! this my greeetings!!!


I ran ur code in vc2005. my pc has win 7..



C#
char * p = "hello";
cout<<p;   // printing the char pointer wihtout any condition
cout<<p+1; // printing the pointer skipping the first character
cout<<*p;// printing the value at the address char p[0]. which is p[0].






I got the following anwser which is as expected:

hello
ello
h

please re-build the project and try again!
 
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